This invention relates to a protective device for floor cleaning apparatus with a rotating driving source and with two rotating brush rollers driven thereby.
Various different processes are employed for the cleaning of textile floor coverings. In the main they are classified as "wet" processes, e.g. "spray extraction", on the one hand, and the so-called dry cleaning processes on the other. These latter are by far the most problem-free methods for the layman, as the risk of puckering due to excessive wetting cannot occur. The dry cleaning of textile floor coverings is effected with a powder containing not only detergents but also solvents and other ingredients. Floor processing machines with rotating foam plastic rollers or brush rollers are used for the purpose of working this powder into the pile of the carpet, so that it can take effect therein.
Already known apparatus of this kind are made, for example, by Vorwerk (Federal Republic of Germany), Host (U.S.A.) and Certified (U.S.A.). The two latter each operate with two brush rollers rotating in opposite directions. These are extremely efficient, i.e. penetrate the pile to an ample depth and clean the fibers from all sides. However, the possibility has to be faced, as in all brush rollers rotating in a housing, that corners or edges of the carpet will be pushed into the housing by the brush rollers and thus suffer damage. This would also choke the floor cleaning apparatus and possibly damage it.
In order to avoid this the customary apparatus has been fitted with protective devices in the form of guard grids which extend across the brush rollers on the side of the latter which is in contact with the floor. These protective grids suffer from serious drawbacks, which reside in the fact that in the first place it is far more difficult to clean and replace the brush rollers, while in the second place the cost of manufacturing and assembling the apparatus is greatly increased. When the brush rollers have to be cleaned and replaced, the protective devices first have to be removed. The protective bars extending across the brush rollers impede operation from yet a further point of view: the bristles on the brush rollers have to be interrupted at the point in question, so that "streaks" are left on the carpet where the roller has "missed" it. Such apparatus therefore fails to ensure maximum evenness in the "raising" of the pile and in the cleaning of the carpeted floor.